Designation B94 − 13 Standard Specification for Magnesium Alloy Die Castings1 This standard is issued under the fixed designation B94; the number immediately following the designation indicates the ye[.]
Designation: B94 − 13 Standard Specification for Magnesium-Alloy Die Castings1 This standard is issued under the fixed designation B94; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision A number in parentheses indicates the year of last reapproval A superscript epsilon (´) indicates an editorial change since the last revision or reapproval This standard has been approved for use by agencies of the Department of Defense E23 Test Methods for Notched Bar Impact Testing of Metallic Materials E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications E88 Practice for Sampling Nonferrous Metals and Alloys in Cast Form for Determination of Chemical Composition E505 Reference Radiographs for Inspection of Aluminum and Magnesium Die Castings E527 Practice for Numbering Metals and Alloys in the Unified Numbering System (UNS) 2.3 American Die Casting Institute:3 “E” Series Product Standards 2.4 Federal Standards:4 FED-STD-123 Marking for Shipment (Civil Agencies) SAE AMS-STD-184 Identification Marking of Aluminum, Magnesium and Titanium 2.5 Military Standard:4 MIL-STD-129 Marking for Shipment and Storage Scope* 1.1 This specification covers magnesium-alloy die castings Current alloy compositions are specified under the designations shown in Table 1.2 1.2 The values stated in inch-pound units are standard The SI values in parentheses are provided for information only 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use Referenced Documents 2.1 The following documents of the issue in effect on date of order acceptance form a part of this specification to the extent referenced herein: 2.2 ASTM Standards:3 B93/B93M Specification for Magnesium Alloys in Ingot Form for Sand Castings, Permanent Mold Castings, and Die Castings B557 Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products B660 Practices for Packaging/Packing of Aluminum and Magnesium Products B951 Practice for Codification of Unalloyed Magnesium and Magnesium-Alloys, Cast and Wrought B953 Practice for Sampling Magnesium and Magnesium Alloys for Spectrochemical Analysis B954 Test Method for Analysis of Magnesium and Magnesium Alloys by Atomic Emission Spectrometry Terminology 3.1 Definitions: 3.1.1 die casting—a metal object produced by the introduction of molten metal under substantial pressure into a metal die and characterized by a high degree of fidelity to the die cavity Ordering Information 4.1 Orders for die castings shall include the following basic information: 4.1.1 This specification number and date, 4.1.2 Quantity and delivery schedule, as required, 4.1.3 Part name and number, 4.1.4 Alloy (Table 1), and 4.1.5 Drawing of die casting, when required, giving all necessary dimensions and showing latest revisions and allowances for machining, if any Location of ejector pin marks or parting lines shall be at the option of the producer, unless specifically designated on the drawing This specification is under the jurisdiction of ASTM Committee B07 on Light Metals and Alloys and is the direct responsibility of Subcommittee B07.04 on Magnesium Alloy Cast and Wrought Products Current edition approved May 1, 2013 Published June 2013 Originally approved in 1934 Last previous edition approved in 2007 as B94 – 07 DOI: 10.1520/B0094-13 SAE specifications No 501 and 501A conform to the requirements for Alloy AZ91A and AZ91B respectively For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website Available from Standardization Documents Order Desk, DODSSP, Bldg 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:// www.dodssp.daps.mil *A Summary of Changes section appears at the end of this standard Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959 United States B94 − 13 TABLE Chemical RequirementsA,B,C,D Alloy DesignationB Composition, % UNS Aluminum Manganese Rare Earth Strontium Zinc Copper, max Iron, max Silicon AS41A M10410 3.5-5.0 0.20-0.50 0.12 0.06 AS41B M10412 3.5-5.0 0.35-0.7E 0.12 0.02 0.0035E E AM50A AM60A AM60B AZ91A M10500 M10600 M10602 M11910 4.4-5.4 5.5-6.5 5.5-6.5 8.3-9.7 0.26-0.6 0.13-0.6 0.24-0.6E 0.13-0.50 AZ91B M11912 8.3-9.7 0.13-0.50 AZ91D F AJ52A AJ62AF AS21A AS21BF M11916 M17520 M17620 M10210 M10212 8.3-9.7 4.5-5.5 5.5-6.6 1.8-2.5 1.8-2.5 0.150.50E 0.24-0.6E 0.24-0.6E 0.18-0.7 0.05-0.15 0.060.25 1.7-2.3 2.0-2.8 0.22 0.22 0.22 0.351.0 0.351.0 0.351.0 0.22 0.22 0.20 0.25 0.010 0.35 0.010 0.10 0.004 0.005E 0.501.5 0.501.5 0.10 0.50 0.10 0.50 0.35 0.030 0.010 0.010 0.01 0.008 E Nickel Other Magnesium Metallic Impurities, max, each 0.03 remainder 0.002 0.02 remainder 0.002 0.03 0.002 0.03 0.02 0.02 remainder remainder remainder remainder 0.50 0.03 remainder E 0.10 0.002 0.02 remainder E 0.10 0.10 0.7-1.2 0.7-1.2 0.001 0.001 0.001 0.001 0.01 0.01 0.01 0.01 remainder remainder remainder remainder 0.005 0.004 0.004E 0.005 0.0035 A Analysis shall regularly be made only for the elements specifically mentioned in this table If, however, the presence of other elements is suspected or indicated in the course of routine analysis, further analysis shall be made to determine that these other elements are not in excess of 0.3 % B The following applies to all specified limits in this table: For purposes of acceptance and rejection an observed value or a calculated value obtained from analysis should be rounded to the nearest unit in the last right-hand place of figures used in expressing the specified limit in accordance with the rounding procedure prescribed in Section of Practice E29 C Where single units are shown, these indicate the maximum amounts permitted D ASTM alloy designations were established in accordance with Practice B951, UNS designations were established in accordance with Practice E527 E In alloys AS41B, AM50A, AJ52A, AM60B, AJ62A, and AZ91D, if either the minimum manganese limit or the maximum iron limit is not met, then the iron/manganese ratio shall not exceed 0.010, 0.015, 0.015, 0.021, 0.021, and 0.032, respectively F Alloys AJ52A, AJ62A, and AS21B are patented compositions for elevated temperature applications Interested parties are invited to submit information regarding the identification of alternatives to these compositions to ASTM International Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility sible for the performance of all inspection and test requirements specified herein Except as otherwise specified in the contract or order, the producer or supplier may use his own or any other suitable facilities for the performance of the inspection and test requirements specified herein, unless disapproved by the purchaser The purchaser shall have the right to perform any of the inspections and tests set forth in this specification Quality assurance standards shall be agreed upon between the producer or supplier and purchaser at the time a contract or order is placed 4.2 Additional tests, options, and special inspection requirements as provided below should be justified only on the basis of need These shall be specified in the contract or purchase order, as additional procedures and extended delivery time may be involved 4.2.1 Chemical analysis (7.1.1), 4.2.2 Quality assurance (Section 6), 4.2.3 Special proof tests or mechanical properties (Section 8), 4.2.4 General quality options for internal soundness or for finish (Section 10), 4.2.5 Source inspection (Section 11), 4.2.6 Certification (Section 12), 4.2.7 Marking for identification (Section 14), and 4.2.8 Special packaging (Section 15) 6.2 Lot Definition—An inspection lot shall be defined as follows: 6.2.1 An inspection lot shall consist of the production from each die or compound die on each machine for each 24 h during the first week of normal operation and the production for each 48 h thereafter of normal operation Any significant change in the machine, composition, die, or continuity of operation shall be considered as the start of a new lot Die castings inspected by this method shall be so marked or handled during the finishing operations as not to lose their identity 6.2.2 Each die casting of a randomly selected sample shall be examined to determine conformance to the requirements with respect to general quality, dimensions, and identification Materials 5.1 The magnesium alloys used for the manufacture of die castings shall be such that the die castings produced will conform to the chemical composition requirements of this specification Ingot in accordance with Specification B93/ B93M may be used but is not restricted to this source Quality Assurance 6.1 Responsibility for Inspection—When specified in the contract or purchase order, the producer or supplier is respon- B94 − 13 Permissible Variations in Dimensions marking The producer or supplier may use a system of statistical quality control for such examinations 9.1 Permissible variations in dimensions shall be within the limits specified on the drawings or in the contract or purchase order 9.1.1 Any dimensions for which a tolerance is not specified shall be in accord with ADCI Product Standard Series E1 to E16 “E” Series Product Standards inclusive Chemical Composition 7.1 Limits—The die casting shall conform to the requirements as to chemical composition prescribed in Table Conformance shall be determined by the producer by analyzing samples taken at the time castings are made If the producer has determined the chemical composition of the metal during the course of manufacture, he shall not be required to sample and analyze the finished product 7.1.1 When a detailed chemical analysis is required with a shipment, it shall be called for in the contract or purchase order 7.1.2 If the producer’s or supplier’s method of composition control is acceptable, sampling for chemical analysis may be waived at the discretion of the purchaser 9.2 Dimensional tolerance deviations waived by the purchaser shall be confirmed in writing to the producer or supplier 10 General Quality 10.1 Internal Soundness—When specified, the soundness of die castings shall conform to standards or requirements agreed upon between the producer or supplier and the purchaser The number and extent of imperfections shall not exceed those specified by the purchaser The standards or requirements may consist of radiographs in accordance with Reference Radiographs E505, photographs, or sectioned die castings 7.2 Number of Samples—When required, samples for determination of chemical composition shall be taken to represent the following: 7.2.1 A sample shall be taken from each of two representative castings selected from each lot defined in Section 6.2.1 10.2 Imperfections inherent in die castings shall not be cause for rejection provided it is demonstrated that the die castings are in accordance with the requirements and standards agreed upon 7.3 Methods of Sampling—Samples from die castings for determination of chemical composition shall be taken in accordance with one of the following methods: 7.3.1 Samples for chemical analysis shall be taken from the material by drilling, sawing, milling, turning, or clipping a representative piece or pieces to obtain a weight of prepared sample not less than 75 g Sampling shall be in accordance with Practice B953 7.3.2 By agreement, an appropriate spectrographic sample may be prepared at time of manufacture 7.3.3 The method of sampling cast products for spectrochemical and other methods of analysis shall be suitable for the form of material being analyzed and the type of analytical method used 10.3 Workmanship—Die castings shall be of uniform quality, free from injurious discontinuities that will adversely affect their serviceability 10.4 Finish—When specified in the contract or purchase order the as-cast surface finish required shall conform to standards agreed upon between the purchaser and the producer or supplier, or as prescribed in ADCI Product Standard E18 “E” Series Product Standards 10.5 Pressure Tightness—When specified in the contract or purchase order the pressure tightness of die castings shall conform to standards agreed upon between the purchaser and the producer or supplier, or as prescribed in ADCI Product Standard E17 “E” Series Product Standards 7.4 Method of Analysis—The determination of chemical composition shall be made in accordance with suitable chemical, spectrochemical (Test Method B954), or other methods In case of dispute, the results secured by Test Methods B954 shall be the basis of acceptance 11 Source Inspection 11.1 If the purchaser desires that his representative inspect or witness the inspection and testing of the product prior to shipment, such agreement shall be made by the purchaser and producer or supplier as part of the contract or purchase order Mechanical Properties and Tests 11.2 When such inspection or witness of inspection and testing is agreed upon, the producer or supplier shall afford the purchaser’s representative all reasonable facilities to satisfy him that the product meets the requirements of this specification Inspection and tests shall be conducted so there is no unnecessary interference with the producer’s operations 8.1 Unless specified in the contract or purchase order or specifically guaranteed by the manufacturer, acceptance of die castings under these specifications shall not depend on mechanical properties determined by tension or impact tests Tables X1.1 and X1.2 show typical mechanical properties and characteristics When tension or impact tests are made, the tension test specimen shown in Fig 13 of Methods B557, and the impact test specimen shown in Fig of Test Methods E23 shall be used 12 Rejection and Retest 12.1 When one or more samples, depending on the approved sampling plan, fail to meet the requirements of this specification, the represented lot is subject to rejection except as otherwise provided in 12.2 8.2 When specified in the contract or purchase order, die castings shall withstand proof tests without failure as defined by agreement between the purchaser and the producer or supplier 12.2 Lots rejected for failure to meet the requirements of this specification may be resubmitted for test provided: B94 − 13 normal handling and transportation Each package shall contain only one type of item unless otherwise agreed upon The type of packaging and gross weight of containers shall, unless otherwise agreed upon, be at the producer’s discretion, provided they are such as to ensure acceptance by common or other carriers for safe transportation at the lowest rate to the delivery point 12.2.1 The producer has removed the nonconforming material or the producer has reworked the rejected lot as necessary to correct the deficiencies 12.3 Individual castings that show injurious imperfections during subsequent manufacturing operations may be rejected The producer or supplier shall be responsible only for replacement of the rejected castings to the purchaser As much of the rejected original material as possible shall be returned to the producer or supplier 15.2 Marking—Each shipping container shall be legibly marked with the purchase order number, gross and net weights, and the supplier’s name or trademark Marking for shipment shall be in accordance with FED-STD-123 for civil agencies and MIL-STD-129 for Military agencies 13 Certification 13.1 The producer or supplier shall, when called for in the contract or purchase order, furnish to the purchaser a certificate of inspection stating that each lot has been sampled, tested, and inspected in accordance with this specification, and has been found to meet the requirements specified 15.3 Preservation—Material intended for prolonged storage in unheated locations shall be adequately packed and protected to avoid deterioration and damage When specified in the contract or purchase order, material shall be preserved, packaged, and packed in accordance with the requirements of Practices B660 The applicable levels shall be as specified in the contract or order 14 Product Marking 14.1 When specified in the contract or purchase order, all castings shall be properly marked for identification with the part number, name or brand of the producer, as agreed upon Government applications shall be marked in accordance with SAE AMS-STD-184 16 Keywords 16.1 casting characteristics; composition; high pressure die cast alloy; magnesium; mechanical properties; performance characteristics 15 Packaging, Marking, and Storage 15.1 Packaging—Unless otherwise specified, the die castings shall be packaged to provide adequate protection during APPENDIXES (Nonmandatory Information) X1 MECHANICAL PROPERTIES AND CHARACTERISTICS not exceed 100 ksi (700 MPa)/min Exceedingly slow rates of testing may result in creep and hence are to be avoided Beyond the yield strength, the rate of straining shall not exceed 0.25 in./in · min, measured on the gage length of the specimen It should be thoroughly understood that the figures in the table represent die-cast test specimens and not specimens cut from commercial die-cast parts X1.1 Table X1.1 shows certain casting and other outstanding characteristics which are usually considered in selecting a magnesium die casting alloy for a specific application A No rating is the highest X1.2 The use of separately die-cast test bars was omitted from this specification revision because they are considered unreliable Different machines and dies continue to be necessary for die castings and test bars Comparison between static breakdown or proof test and the mechanical properties of separately die-cast test bars revealed that test bars made in a different machine in a different die had no correlation with the die casting, other than a common chemical composition For this reason, it is considered that the only practical method is to have mechanical property control based on proof testing of whole die castings For information only, typical separately die-cast specimen tensile properties are presented in Table X1.2 These properties are of tension specimens of the form and dimensions shown in Fig 13 in Methods B557 and Fig of Test Methods E23, when cast in a die in regular production routine and conforming to the chemical composition specified in Table In the tension testing of magnesium alloy specimens, the rate of stressing up to the yield strength shall X1.3 Alloy AM60A has a specific gravity of about 1.78 It is suggested for use for those applications requiring a combination of good elongation, yield strength, and tensile strength X1.4 Alloy AS41A has a specific gravity of about 1.78 The alloy possesses good room temperature elongation, yield strength, and tensile strength At temperatures up to about 350° F (175° C) it has a much increased creep resistance over Alloys AZ91A, AZ91B, and AM60A Maximum resistance to creep is obtained at the lower aluminum content X1.5 Alloys AZ91A and AZ91B have a specific gravity of about 1.81 The copper and nickel contents in AZ91A should be kept low to minimize corrosion The corrosion resistance of Alloy AZ91B is decreased by the higher copper content and die castings made from this alloy should be used under a known B94 − 13 TABLE X1.1 Die Casting and Other Characteristics Alloy UNS ASTM M10500 AM50A M10600 AM60A M10410 AS41A M10412 AS41B M11910 AZ91A M11912 AZ91B M11916 AZ91D M10602 AM60B M10502 AJ52A M10604 AJ62A M10200 AS21A M10202 AS21B Approximate Melting Range, °F (°C) Resistance to Cold DefectsA Pressure Tightness Resistance to Hot CrackingB MachiningC ElectroplatingD Surface TreatmentE Strength at Elevated TemperaturesF 1025–1145 (551–618) 1005–1140 (540–615) 1050–1150 (565–620) 1050–1150 (565–620) 875–1105 (470–595) 875–1105 (470–595) 875–1105 (470–595) 1005–1140 (540–615) 957-1144 (514-618) 957-1135 (514-613) 815-1170 (435-632) 815-1170 (435-632) 3G 1G 2G 1G 2G 1G 3G 3G 1G 2G 1G 2G 1G 4G 1G 1G 1G 2G 1G 4G 1G 1G 1G 2G 1G 2 2 2 2 2 2 2 3G 1G 2G 1G 2G 1G G G G G G G G G 1G 1G 1G 2G 1G 2 1G 1G 1G 2G 1G A The ability of alloy to resist formation of cold defects; For example, cold shuts, cold cracks, non-fill “woody” areas, swirls, etc Ability of alloy to withstand stresses from contraction while cooling through the hot-short or brittle temperature range Composite rating based on ease of cutting, chip characteristics, quality of finish and tool life D Ability of the die casting to take and hold an electroplate applied by present standard methods E Ability of castings to be cleaned in standard pickle solutions and to be conditioned for best paint adhesion F Rating based on resistance to creep at elevated temperatures G Rating based upon limited experience, given guidance only B C TABLE X1.2 Typical Properties of Magnesium Alloy Die-Cast Test SpecimensA Property/UNS Alloy Tensile strength, ksi (MPa) Tensile yield strength, ksi (MPa) Compression yield strength, ksi (MPa) Elongation in in (50 mm), percent Impact, ft·lbB (J) Shear strengthC , ksi (MPa) Fatigue strengthD , ksi (MPa) Brinell hardness Rockwell hardness, F scale M100500AM50A M10600AM60A M10602AM60B M10410AS41A M10412AS41B M11910-AZ91A M11912-AZ91B M11916-AZ91D M10502AJ52A M10604AJ62A M10200AS21A M1010202AS21B 29 (200) 16 (110) 10 58 32 (220) 19 (130) 62 31 (210) 20 (140) 34 (230) 23 (160) 23 (160) (3) 20 (140) 14 (100) 63 75 32 (221) 20 (141) 13 (90) (7.4) (60) 60 34 (232) 20 (141) 15 (105) 10 (13.3) 12 (80) 61 33 (230) 17 (120) 15 (106) 12 3.7 (5) 55 34 (231) 18 (122) 15 (106) 13 3.7 (5) 55 A ksi = 1000 psi For explanation of SI unit MPa see Appendix X2 Unnotched Double-shear tests converted to single-shear values D × 108 cycles B C range of atmospheric conditions for which their life can be considered satisfactory X1.7 Alloy AM50A is a high purity alloy with corrosion resistance similar to AM60B, but with improved ductility due to the reduced level of aluminum content X1.6 Alloys AS41B, AM60B, and AZ91D are high purity versions of AS41A, AM60A, and AZ91B As a result they have improved resistance to salt-water (aqueous NaCl) corrosion X1.8 Alloys AJ52A and AJ62A are alloy compositions based on aluminum and strontium additions for improved creep B94 − 13 resistance and tensile properties at elevated temperatures relative to AS alloys the corrosion resistance of these alloys is competitive with the high purity alloys above The AJ62A composition has improved castability with slightly reduced creep resistance relative to AJ52A X1.9 Alloys AS21A and AS21B have improved creep resistance and tensile properties relative to the AS41A and AS41B alloys Both alloys possess good castability and ductility The AS21B alloy is a modified composition with salt water corrosion resistance equivalent to the high purity alloys X2 METRIC EQUIVALENTS stress is the newton per square metre (N/m2), which has been named the pascal (Pa) by the General Conference on Weights and Measures Since ksi = 894 757 Pa the metric equivalents are expressed as megapascal (MPa), which is same as MN/m2 and N/mm2 X2.1 The SI unit for strength properties (MPa) is in accordance with the International System of Units (SI) The derived SI unit for force is the newton (N), which is defined as that force which when applied to a body having a mass of one kilogram gives it an acceleration of one metre per second squared (N = kg·m/s2) The derived SI unit for pressure or SUMMARY OF CHANGES Committee B07 has identified the locations of selected changes to this standard that have been incorporated since the last issue (B94 – 07 (Approved May 1, 2013) (1) Replaced withdrawn Test Methods E35 with Practice B953 and Test Method B954 (2) Replaced cancelled FED-STD-184 with superceding SAE AMS-STD-184 ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility This standard is subject to revision at any time by the responsible technical committee and must be 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